There's only one thing in the chapter I had trouble reading after scaling it all down with the reader settings until it looked better, but it was still possible to read it at that point I guess. Try fit width and limiting the width to 600. It's just that first actual page's "A JK who obsesses over everything her elementary schooler says" that was kind of tricky, so I would say there's probably a better solution like putting it in the margin with a larger font or something? Sacrificing the entire chapter's quality seems like a weird choice for one of those little non-bubble pieces of additional dialogue.